Technical Field
The exemplary and non-limiting embodiments relate generally to cutting wafers, and more specifically, to selective partial dicing of either a semiconductor wafer or a glass wafer using a laser emitting a laser beam.
Brief Description of Prior Developments
During the processing of semiconductor wafers it can be advantageous to support the semiconductor wafer on a substrate wafer. In the case where the semiconductor wafer is a silicon wafer a glass substrate wafer may be used. Generally the silicon wafer is bonded to the glass wafer using either an adhesive or double-sided tape.
It is usually desirable to dice the silicon wafer into individual dies. This is conventionally accomplished by using a mechanical saw blade covered with an abrasive such as diamond dust. Dicing of a silicon wafer laminated on a glass support wafer using a saw blade can damage the support wafer due to a lack of accuracy in controlling the depth of the cut. Another issue is caused by variations in the thickness of the silicon wafer and the glass wafer at their interface. The damage to the glass wafer can prevent it from being reused. In some circumstances it may be desirable to only dice the glass wafer without damaging the silicon wafer. Using a saw blade in this situation has the same issues as discussed above.